/*
* Copyright (C) 2009-2015 Max Kellermann <max@duempel.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef THREAD_POSIX_COND_HXX
#define THREAD_POSIX_COND_HXX
#include "PosixMutex.hxx"
#include <sys/time.h>
/**
* Low-level wrapper for a pthread_cond_t.
*/
class PosixCond {
pthread_cond_t cond;
public:
#ifdef __GLIBC__
/* optimized constexpr constructor for pthread implementations
that support it */
constexpr PosixCond():cond(PTHREAD_COND_INITIALIZER) {}
#else
/* slow fallback for pthread implementations that are not
compatible with "constexpr" */
PosixCond() {
pthread_cond_init(&cond, nullptr);
}
~PosixCond() {
pthread_cond_destroy(&cond);
}
#endif
PosixCond(const PosixCond &other) = delete;
PosixCond &operator=(const PosixCond &other) = delete;
void signal() {
pthread_cond_signal(&cond);
}
void broadcast() {
pthread_cond_broadcast(&cond);
}
void wait(PosixMutex &mutex) {
pthread_cond_wait(&cond, &mutex.mutex);
}
bool timed_wait(PosixMutex &mutex, unsigned timeout_ms) {
struct timeval now;
gettimeofday(&now, nullptr);
struct timespec ts;
ts.tv_sec = now.tv_sec + timeout_ms / 1000;
ts.tv_nsec = (now.tv_usec + (timeout_ms % 1000) * 1000) * 1000;
return pthread_cond_timedwait(&cond, &mutex.mutex, &ts) == 0;
}
};
#endif
